Impulse control device



Feb.20, 1951 awcHAplN 2,542,626

IMPULSE CONTROL DEVICE Filed Sept. 28,1945 2 Sheets-Sheet l p. Jig-1 ll 4/ 35 a 36 L e ii 61 171/ a M J J y-mi? A w 15 1 141 1 l 66 14 &5

INVENTOR'. Bryan Feb. 20, 1951 B. w. CHAPlN IMPULSE CONTROL DEVICE 2 Sheets-Sheet 2 Filed Sept. 28, 1945 CO/L MOT/0N -INVEN TOR. firyazzyfzapm BY Z fizzy Patented Feb. 20, 1951 UNITED STATES newsman IMPULSE CONTROL DEVICE Bryan W. Chapin, Bloomingdale, N. Y., assignor to Production Instrument Company, Chicago, 111., a corporation of Illinois Application September 28, 1945, Serial No. 619,184

24 Claims. (01. 185-46) This invention relates to sensitive high speed impulse control devices. and is particularly con-- cerned with a novel escapement mechanism forapparatus being shown partially in section and partially in elevation;

Fig. 2 represents an enlarged transverse sectional view of the escapement mechanism as seen along lines 22 in Fig. 1;

Fig. 3 is a diagram showing the escapement mechanism rolled out in a horizontal plane to illustrate the relative position of certain parts and to explain their coaction;

Fig. 4 illustrates the escapement control element partly in elevation and partly in crosssection to bring out'details; and

Fig. 5 is an exploded view of an elastic coupling employed in the drive of the apparatus shown in Fig. l.

The drawings are more or less diagrammatic,

not to scale, and are intended for descriptive and illustrative purposes only.

Known details and elements will be described only to the extent which is required to bring out the invention.

Like reference numerals denote like parts throughout the drawings. I

The apparatus shown in Fig. 1 comprises the following principal parts: (1) a suitable motor (not shown) for applying torque to a drive shaft H; (2) an elastic or resilient coupling generally indicated at E2 which connects the drive shaft H with the shaft l3; (3) an electromagnet having the core l4 and the coil l5 disposed in the lower part of a circu ar pot-like housing formed by the bottom plate It and a tubular wall l1; (4) the new escapement mechanism generally iridicatedby numeral l8; (5) a gear train com-- prising the bevel gears iii-29 and the gear wheel" 2!; and (6) a gear wheel 22 for operating number wheels diagrammatically shown at 23 mounted on a shaft 25.

The arrangement pr'ovidesa control for the rotation of the shaft 13 in successive angular increments determined by the escapement IS in accordance with impulses produced at a desired source which is represented by the battery 25 andthe impulse contact 26. The bevel gear I9 is thus."

rotated, operating the bevel gear 28 to rotate the shaft 2'! and gear wheel 2!, the latter meshing with the gear wheel 22 to actuate the number wheels 23 so as to display through a sight or index opening in a suitable cover the row of numbers which correspond to and indicate at any time the total number of impulses received from the impulse source 2526. The cover has been'omitted in order to keep the drawing simple.

Details of the structure and operation will now. be described with reference to Figs. 1-5, inclusive.

The housing is made of the tubular wall I l and the bottom plate I6 which is held in engagement with the wall [-1 by press-fit. Both the tubular wall and the bottom plate are made of soft iron. The core 14 is likewise held by press-fit in the bottom plate Hi. In the annular space between the core I4 and the wall I! are disposed the windings of coil 15. The coil terminals are connected to conductors 28--29 which terminate in switch 30. The latter is adapted to connect the coil terminal conductors with the terminals of a battery 3i.- Direct current can thus be supplied to the windings of coil l5.

The drive control structure of the escapement mechanism, which is effected by the displacement of the coil 34, is mounted centrally of the doublewall bellows-like diaphragm having the diaphragm disks 3536. The peripheral flanges of these disks aredisposed on the annular rim formed by the top edge of the tubular housing wall l1 and are clamped thereon by a ring-like member 3'5. Each diaphragm disk is provided with a central opening. The diaphragm disk 35 is attached at the rim of its central opening to the flan e 38 of a tubular member 39 and the diaphragm disk 36 is centrally attached to the flange 49 of the"tubular member M. These tubular members also carry flanges 42-43, respectively (see also Figs. 2 and 4), and mounted between these flanges and held thereby is a ringlike member 44. The flanges 42-43 are for'this purpose peened or rolled over the ring-like mem-. ber 44 and suitably attached to it. The tubular 5- flanged members 39 and 4| may be made of lightweight metal, for" example, aluminum, and the ring-like member may be made of brass. These materials are noted for the purpose of giving examples; other materials may, of course, be

used. It is important, however, that the structure be as light-weight or featherweight as possible. The attachment of the ring-like member 44 may be secured to the flanges 4243 in any desired and approved: manner, for example, by Welding, brazing or riveting. The ring-like memthat the featherweight escapement drive control structure comprising the tubular members39;and

4| and the ring-like member 44, which carries the twenty radially inwardly extending pin-like.

projections 15, is elastically positioned, for oscillation in axial direction, by the peripherally,

mounted diaphragm disks -36, and that its lower part carrying the coil. 34extendsinto the annular gap 33 formed b the core- 14. andthe central opening in'the plate 32. A. coiled spring 501s disposed-within the tubular drive control-as shown inFig. 1. The lower-most turn of this spring is positioned in a groove providedinthe.

core i l on top thereof, and the uppermost turn.

engages the drive control-extensions-of pins projecting radially inwardly from the ring 64.

The escapement drive control is. thusresiliently or elastically biased in axial direction andis held in the normal position inwhich it is shown-in the drawing Fig. l.

Assuming'that current -is connectedto the terminals ofthe: coil I5 of the electromagnetand. that an impulse is delivered. tothe. windings-34 of the coil carried between the flanges 84 'l of.

the esoapement drive control; by the actuation of the contact 28, the coil 34 willbe pulled downwardly into thegap 33, thereby axially displacing.

the light-weight drive-controlstructure comprising thetubular members-M, 39 and the ring -like member-M- with its'pins 45. Such displacementwill be against the pressureof thespring and against the tendency of.- the: diaphragm disks 3536 to' keep the parts in the-normal position shown in Fig. 1. The downward impact of the drive control structure is cushionedaby anelastic member, 9. g., a rubber washer. 5L. disposed atthe bottom ofthe gap33: When theimpulse con 8 tact 25 is opened, current is disconnected from the windings of coil. 34; and the-drive, control structure is returned to its' normal position by the pressure of'the'spring 50 and-by thetendency of the diaphragm disks to maintain thepartsin The up the normal position shown inFig. 1; ward impact at the end of the return motion is cushioned by an-elastic. member EZ Which'may-bea rubber washer secured to thebottom of the cover plate 53. The escapement drive control structure is thus resiliently or elastically mounted for movement axially in eitherdirection and its displacement is elastically cushionedat the end of its motion in either direction.

Two side plates or arms litextendupward Rotatably; mounted in these side plates is th shaft 21 carrying the- Numerals 56-6! indicate ly from the cover plate 53.

bearing inserts for-the shaft 27. Also mounted in theside plates 5-i-55' is the counting device comprising the shaft 24, number wheels diagrammatically indicated at 23, and the gear wheel 22:

which meshes with'the gearwheel 2|. Numerals 58-59 indicate. bearings for the. shaft of; the

number wheels;

The counting device is shown Wholly diagrammatically. It is understood that the mechanism may comprise any desired number of numeral wheels such as 23, and that transfer means are provided for advancing the wheels of higher numerical order responsive to the advance of the adjacent wheels of lower order to certain numerical positions, as is well known from such counting mechanisms. Each number wheel isperipherally provided with numerals from 1 to 0. Assuming that all wheels are in angular alignment, that is, that they are in zero position so far as the sight or index opening is concerned, and that the units number. wheel shown directly at the left of. the gearwheel'ZZis rotated one full revolution, itL- will successively displa through the sight or indexopening of the cover the numerals 1 to 9, and finally again the numeral 0. The units numberwheel. therefore advances in increments of one-tenth of a revolution. The one-tenth revolution. of theunitswheel, which brings it. back to 0,, causes. actuationof. the transfer mechanism,,

and the tens number wheel then rotates todisplay numerall.. Thedevice-will now display the.

number 10. Twov full revolutions of the units wheel produce for display thenumber 20. Sue-- cessively high numbers are. thus set by the rotationof the units-wheel. The rotation of the units wheel coincideswith the rotation of the gear wheel 22. The gear wheels 22 and 2| are of identical structure and the ratio between these gear w-heelsvis therefore i 1.

The object of the mechanism is to control the rotation of the number wheels.23 so as to record or count the number of impulses produced at the impulse. source 2526. Each impulse consisting of a closure of contact 26 and subsequentopening.

thereof must therefore produce a one-tenth revolution-of thegear wheel 2-2 and therewith alone.-

tenth revolutionof the units number wheel. Thebevel gear l9 carried on top-of the shaft 13-. is

provided: with; twice the number of teethas the bevelgear 20: and the ratio-between these bevel gears is thereforelzZ. It follows that the rotation of the shaft I 3* must. be controlled in: incrementsof 18 angular displacement correspondingv to twenty increments for each full revolution. The shaft 21 and the gear wheels 2i22 will then be rotatedin increments of 36, or one-tenth of arevolution to. each 18 displacement. or one twentieth of a revolutionof the shaft l3. Each one-tenth, revolution of the gear. wheel 22 and therewith of units wheel 23 thus advances the counter by one number.

In order to obtainthe operations outlined above, I have provided a rotatably mounted escapement element which coacts with the twenty pins 45 projecting radially inwardly from the ring-like member 44 of the previously described featherweight escapement drive control. The rotatable element comprises a cross-sectionally H-shaped member having the flanges 60 and, BI: interconnected by the central'tubular member 80. The latter. may be: split and suitably assembledto" form the flanged element shownin.

the drawings. Theelement is freely rotatabIe'on the shaft l3 and is heldthereon against; axial displacement by split rings shown in Fig. 1, which engage grooves on the shaft 13. The flange 60 carries twenty control extensions or projections made in the form of pinlike members 62 which are annularly arranged thereon and project axially therefrom, and the flange 61 also carries twenty similarly disposed extensions made in the formof pinlike members 63; These pinlikemembers are staggered by increments of 9 and overlap axially a slight amount, as shown in Fig. 3. These two opposed annular rows of pinlike control members 6263 projecting from the flanges 60-6l are intercepted by the twenty pinlike control members 45 which project radially inwardly from the ring-like member 44 of the escapement drive control. Rotation of the ele ment carrying the flanges 60-61 centrally interconnected by the tubular member' 80 is thus normally inhibited. The element is resiliently or elastically coupled with the shaft 13 by a spring 64 one end of which is anchored in the flange 6| and the other in the shaft I3, as shown in Fig. 1. Rotation of the shaft I3 in normal position of the escapement is thus' likewise inhibited.

The shaft 13 is journalled in suitable bearings 6566 provided in the core 14 and the bottom plate I6, respectively. Displacementof the shaft l3 axially downwardly is prevented by the bushing part of the bevel gear l9 and axially upwardly by the flange 51 of the elastic coupling I2 shown at the bottom of the structure, as seen in Fig. 1.

The elastic or resilient coupling comprises an upper bushing-like member having the shank 68 and the flange 61 which isfirmly attached to the lower end of shaft I3. This lower end of the shaft is provided with a slot 69 (see Fig. 5) and the shank B8 is provided with a similar slot '10. A coacting lower bushing member having the reduced or stepped-down shank 'H12 and the flange T3 is provided with a slot [4. This coacting bushing is firmly attached to the upper end of the shaft l I which is likewise slotted, as shown in Fig. 5 at 8!. The shank 68 of the upper bushing is placed on the reduced portion 12 of the lower bushing and is thus rotatable thereon. A coiled spring 15 is placed around the shanks 68, H of the bushings, as shown in Fig. 1. upper end 16 of the spring 75 (see Fig. 5) is bent inwardly and is placed in the slot of the shank 68 of the upper bushing, and the lower end 1! of the spring is likewise bent inwardly and is placed into the slot 14 of the shank of the lower bushing. The upper end 16 of the spring is in the assembled structure of the coupling disposed in the slot 69at the lower end of the shaft l3 and the lower end I! of the spring is similarly disposed in the slot 8| in the upper end of the lower shaft II.

The entire device may be easily withdrawn from the elastic coupling, simply by releasing the screw in the flange 67 of the upper bushing, thus releasing the shaft 13, whereupon the device can be withdrawn from the coupling. The insertion or assembly with the main drive of the apparatus is effected by operations in reverse order; that is to say, the lower end of the shaft I3 is simply inserted in the upper bushing having the flanges til-68 until the slot 69 in the shaft is properly aligned with the upper end 15 of the spring 15, whereupon the shaft I3 is dropped. into the coupling and the screw in the flange 61 of the bushing is tightened.

Torque is applied to the shaft H in the direction of the arrow shown in Fig.1. The torque is effective to rotate the lower bushing having the flange l3 and the shanks 'H!2, and is elastically transmitted through the medium of the spring 75 to the upper bushing having the shank 68 and the flange 51. The upper bushing is firmly attached to the shaft [3, and the torque is thus elastically or resiliently transmitted to the shaft. The shaft I 3 transmits the tor ue The elastically or resiliently to the rotatable escapement element having the flanges 60-6! through the medium of the spring 64. The rotatable escapement element thus tends torotate, but is prevented from rotating by the pinlike members 45 of the escapement drive control element which, in the position in which the apparatus is shown in the drawings, interce t the pinlike control members 62 projecting axially downwardly from its flange 60. The relative positions of the parts, at this moment of operation, are shown in Figs. 2 and 3. axially upwardly from the flange Bl of the rotatable escapement element are not affected because the escapement drive control carrying the pinlike members 45 is in its normal raised position, as shown in Fig. 1. Torque applied to the shaft ll thus cannot become eifectiveand does not result in rotation of the shaft l3.

The operation of the device, for the purpose of counting impulses received from the impulse source 26, may be prepared by closing the switch to connect current to the windings of the coil 15 of the electromagnet, and by applying torque to the shaft l3 as explained above. The length of the moving coil 34 exceeds the thickness of the plate 32, and the coil therefore extends normally upwardly and out of the gap 33. The coil is positively held in this normal position by the spring 50 which exerts an upward pressure on the rotatable drive control element by engagement with the roots of the radially inwardly directed pinlike members 45 and by the action of the diaphragm disks 35'36, as explained before.

In Fig. 3, the pinlike members of the axially movable escapement drive control element are shown in this normal and preparatory position in section. The torque applied to the shaft l3 presses the pinlike members 62 of the rotatable element against the pinlike members 45, thus preventing rotation thereof and thereby preventing rotation of the shaft i3. The relative position of the parts is particularly apparent from Figs. 2 and 3, the direction of rotation or, rather to say, of the effect of the torque on the shaft l3 being indicated by the arrow.

Current is now applied to the moving coil 34 of the axially movable escapement drive element,

by the first closure of the impulse contact 26 so. that the flux across the gap 33 can become eiTec-- tive to pull the moving coil 34 axially, downwardly, as shown in Fig. 1, thus moving the escapement drive and its radially inwardly projecting pinlike members 45 from the full line shaded position shown in Fig. 3 into the alternate position in which these members 45 are shown in dotted outline. The downward displacement of the axially movable escapement drive element is against the upward pressure of spring 53 and against the tendency of the diaphragm to keep the element in the normal position shown in Fig. l. The impact of the downward movement of the escapement drive element is cushioned, as previously explained, by the elastic member 51 shown at the bottom of the gap 33. The extent of the axial displacement of the coil 34, and therewith of the escapement drive element, corresponds substantially to the difference between the length of the coil 34 and the thickness of the plate 32. The coil 34 thus remains always in the maximum line of flux across the gap 33. As the pinlike members 45 of the axially movable escapement element pass the pinlike members 62 depending from the flange 6B of the rotatable element, they permit the torque on the shaft 13 to become The pinlike members 63 projecting effective. Accordingly,. the; rotatable; element carrying the flanges 6.0-61I rotates in' the: direction of rotation resulting from the'torque applied to shaft l3. The angular: increment of'rotation amounts to 9 when the pinlike members 45- ofthe axially movable escapement element are in their dotted position shown in Fig. 3, in which position they intercept the pinlilze members 83 projecting from the flange 5| of the rtatable element. When the impulse contact 26 is opened again, current is disconnected from the moving coil 3 and this coil and therewith the axially movable escapement' element moves to the normal position in which the parts are shown in Fig. 1. now again in the normal position shown in section in Fig. 3. The upward motion of the pinlike members d5 into the full line shaded position shown in Fig. 3 releases the pinlike members 63 of the rotatable element and thus permits further rotation of the shaft by 9, completing the first increment of rotation of 18. The bevel gear 19 therefore rotates by 18 and, being geared to the bevel gear 20 in a ratio of 1:2, the latter gear and therewith the shaft 2'? and gear wheel 2! rotate by 36?, or one-tenth of a revolution. The gear wheel 2| is in 1:1 ratio with the gear wheel 22 and therefore the counter shaft 24, together with units number wheel, is displaced by 36, or one-tenth of a revolution. If it is assumed that the operation is started from 0 position of the counter, then the units number wheel will. display through the sight or index opening the numeral 1, corresponding to the one full impulse that has been delivered to the apparatus by the closure and subsequent opening of contact 26.

Successive impu ses produced by the operation of the contact therefore cause successive operative axial displacement of the axially movable escapement element, thereby moving coil 3 and the pinlike escapement drive members in one axial direction followed by axial return to normal position in the opposite direction. Every full impulse thus permits the torque applied to the shaft [3 to become effective to rotate the shaft i3, and therewith the bevel gear [9 by 18 and, due to the gearing, to rotate the shaft 24 and the units number wheel by 36, or one-tenth of a revolution. Each impulse thus advances the units number wheel by one-tenth of a revolution or, in other words, from one numerical position to the next higher numerical position. The tenth full impulse delivered to the device brings the units wheel back to 0 position and at the same time advances the tens wheel to display number I. The transfer may be effected by means of the usual Geneva movement transfer mechanism provided in numerical counters having number wheels as shown in Fig. 1. The last impulse in the first group of one-hundred impulses returns the units and the tens wheels to zero and simultaneously advances the third or hundreds number wheel to display numeral 1. The thousandth impulse sets the counter to dis play the number 1000, and so forth. The operation of number wheels of counters is well known, and further explanations are therefore omitted. It should be observed, however, that the operation Off the counter disclosed herein is effected by gear means which advance the units wheels by increments of angular displacement without the use of pawl and ratchet means usually used in counters.

The foregoing explanations complete the de- The pinlike members 45. are

s'cription: of the. structure and operationoiithe apparatus. It is desired, however, to call attention to a number of features which result from the arrangement of parts and their coaction.

The provision of the spring 50, which is positioned on top of the core M of the electromagnet and engages the radially inwardly projecting pinlike members 45v of the rotatable escapement drive control element, is not only intended to return this element to normal position at the cessation of each impulse, when current is disconnected from the moving coil 35, but also to secure the mechanism against inadvertent displacement of its parts by jarring or the like.

The positioning of the moving coil 34 in the maximum line of flux and the provision of the spring 50 secures the positive displacement and actuation of the axially movable escapement element and of its pinlike escapement drive members 45 with respect to the annularly disposed sets of axially extending pinlike members t2 and 33 of the rotatable element. In other words, the maximum flux across the gap 33 is effective to displace the axially movable escapement element with its pinlike drive members 35 in operative direction and the actions of the spring be as well as of the diaphragm disks are effective to return the element positively to normal position. The resulting positively controlled reciprocatory motion of the axially movable escapement element governs rotation or" the shaft by definitely determined positive increments of angular displacement.

The impacts of the axially movable escapement drive element at the end of its operative actuation and at the end of its return to normal, respectively, are cushioned by the elastic members 5i and 52 shown as rubber rings. It is understood that equivalent means may be provided, including spring means.

The escapement and associated parts are shown in Fig. l in vertical position. It is understood that the mechanism may likewise be disposed in horizontal or, in fact, in any desired angular position in which it may have to be used.

The escapement may be operated at high speed and has actually been tested to produce accurate results at a frequ ncy of impulses per second.

Ihe impulse source, for the sake of giving an example, has been shown in the form of a contact 26 which connects current to the moving coil 34 from a battery 25.

The new escapement has been shown and de scribed in connection with a counter of well known type, but may, of course, be used in connection with other devices and apparatus.

Among the various operations in which the invention will be ound useful are numerous high speed counting operations, for example, in connection with totalizer counters and in connection with counters used in the production of zipper parts and, in fact, in connection with any high speed counting operation above the speed of reciprocating magnets. Other fields of application will be found in remote control apparatus, synchronizing equipment and power step-up arrangements which deliver a weak input for the moving coil and result in a strong torque output from the shaft 13.

The structure illustrated in the drawings shows twenty pinlike control members 45 projecting radially inwardly from the axially movable escapementdrive element and likewise two sets of twenty pinlike control members each in the rotatable element. It is understood that twenty pinlike members have been shown for illus'tration only. More or less may be used. As a matter of fact, a single radially inwardly projecting control member such as 45 would be sufficient to furnish the basic escapement control. The use of a plurality of control extensions or projections such as the pinlike members is, however, desirable in order to minimize wear on the parts and to increase the accuracy of the mechanism. The gearing effected by the number of control extensions or projections may likewise be varied. For example, ten extensions or projections in the axially movable escapement element coacting with ten similar extensions or projections in the rotatable element will provide for direct translation of impulses into angular increments of 36 rotation of the shaft E3. The bevel gears l9 and may in such case be made to provide for a ratio of 1:1.

The rotatable escapement element may be provided for rectilinear motion activated by a force applied to the ends thereof.

The new device is accurate and highly sensitive. The masses to be moved are very small and the start-stop operation is always under proper control. The torque output is considerable in spite of the featherweight masses used in the structure.

Changes may be made within the scope spirit of the accompanying claims.

I claim: a

1. An escapement mechanism comprising a rotatable element carrying two radially cxtend-' ing axially spaced flanges, an annular row of pin-like extensions projecting from each flange axially inwardly thereof, a coacting generally tubular escap ment clement disposed around and said rotatable element, and a plurality of pin-.

like extensions projecting from said tubular element radially inwardly thereof in intercepting relationship relative to the annular rows of extensions projecting from said flanges for the purpose of normally inhibitingrotation of said rotatable escapement element.

2. The structure and combination defined in claim 1, together with a shaft extending axially through said rotatable escapement element for rotatably supporting such element, means for elastically coupling said shaft with said rotatable element, and means for applying torque to said shaft which attempts to rotate the shaft and said rotatable element thereon.

3. The structure and combination defined in claim 1, together with means for elastically applying torque to said rotatable element which attempts to rotate such element, and means for axially reciprocating said tubular coacting escapement element for the purpose of periodically altering the intercepting relationship of the radially inwardly projecting extensions thereof with respect to the rows of axially projecting extensions carried by said rotatable element to permit the torque applied thereto to become effective and to rotate such rotatable element.

4. The structure and combination defined in claim 1, together with means for elastically applying torque to said rotatable element which attempts to rotate such element, a tubular extension projecting axially from said coacting tubular element, and means associated with said tubular extension for reciprocating said tubular coacting escapement element to alter the intercepting relationship of the radially inwardly proiecting extensions thereof with respect to the rows of axially projecting extensions carried by said rotatable element to permit the torque applied thereto'to become effective and to rotate such rotatable element.

5. The structure and combination defined in claim 1, wherein the pin-like extensions in each of the flanges of said rotatable element are arranged in axially overlapping and radially angularly staggered relationship.

6. The structure and combination, defined in claim 1, together with means for mounting said coacting tubular escapement element comprising a diaphragm which extends radially outwardly therefrom, and means for peripherally mounting said diaphragm.

'7. The structure and combination defined in claim 1,'together with means for mounting said coacting tubular escapement element comprising a diaphragm which extends radially outwardly therefrom, means for peripherally mounting said diaphragm, means for reciprocating said elastically mounted coacting tubular escapement element, and elastic means for biasing said coacting escapement element in one direction of reciprocation thereof.

8. 'The structure and combination defined in claim 1, together with means for mounting said coacting tubular escapement element comprising a diaphragm which extends radially outwardly therefrom, means for peripherally mounting said diaphragm, means for reciprocating said tubular coacting escapement element with respect to said rotatable element, elastic means for biasing said coacting escapement element in one direction of reciprocation thereof, and means for elastically limiting the motion of said coacting escapement in either direction of reciprocation thereof.

9. Impulse-controlled apparatus comprising a shaft, elastic coupling means connected with said shaft, means for applying torque to said coupling means, a first escapement element having a pair of flanges which project radially therefrom, each flange carrying an annular row of pin-like members which project axially inwardly therefrom, means for elastically mounting said first escapement element on said shaft to transmit the torque thereto which is applied to the shaft, a second tubular escapement element carrying a pluralit of pin-like members which project radially inwardly thereof, means for elastically mounting said second escapement element for axial reciprocation thereof, means for biasing said second escapement element in one direction of its reciprocatory motion to position the radially inwardly directed pin-like members thereon in positive intercepting relationship with the pinlike members projecting axially from one of the flanges of said first escapement element, and means for reciprocating said secondescapement element so as to move the radially inwardly projecting pin-like members thereon alternately into intercepting relationship with the two rows of pin-like members projecting from the flanges of said first escapement element to allow the torque applied to said shaft to become effective and permit rotation.

10. Ari intermittent transmission device comprising a tubular rotatably mounted driven element carrying control means axially extending therefrom, means for applying a substantially steady torque to said driven element which attempts to rotate it, a tubular control element carrying control means radially extending therefrom which normally intercept the control means on said driven element to prevent rotation ther of responsive to the torque applied thereto, and means for axially reciprocating said tubular control element for the purpose of periodically removing the control means thereof out of intercepting relationship with the control means carried by said driven element to allow said torque to become periodically effective to rotate said driven element.

11. The structure and combination defined in claim 10, together with means for elastically mounting said tubular control element for axial reciprocation.

12. The structure and combination defined in claim 10, together with a drive member, means for elastically coupling said tubular driven element with said drive member, and elastic coupling means for applying said torque to said drive member.

13. An escapement mechanism comprising a rotatable first escapement element carrying control means axially extending therefrom, drive means for applying torque to said first escapement element which attempts to rotate it, a second tubular coacting escapement element peripherally surrounding said first escapement element and carrying control means radially inwar-dly extending therefrom which normally interceptthe control means of said first escapement element, whereby torque applied to said first element is normally prevented to become effective for the purpose of normally inhibiting the rotation of said first element, means for axially re 14. The escapement mechanism defined in claim 13, together with means for elastically coupling said drive means with said firstescapement element, a driven member, means for elastically coupling said driven member with said drive means, and means for applying torque to said driven memberfor elastic transmission to aid drive means and to aid first escapement element.

15. The escapement mechanism defined in claim 13, together with means for elastically mounting said second escapement element for axial reciprocation thereof, and means for axially biasing said elastically mounted second escapement element in a normal position axially thereof.

16. In a device of the class described, a rotatably mounted escapement element comprising two radially extending axially spaced flanges, an annular row of control projections extending from each flange axially inwardly thereof, means for applying a substantially steady torque to said rotatably mounted escapement element which attempts to rotate it, a coacting axially movably mounted escapement element disposed around said rotatably mounted element, means for axially reciprocating said axially movable escapement element, and a plurality of control projections extending from said axially movable element radially inwardly thereof in intercepting relationship alternately with the control projections extending axially inwardly from said flanges, incident to axial reciprocation of said axially movable element, to allow said torque to become eiiective for the purpose of rotating said 12 rotatably mounted escapement element by predetermined angular increments of rotation incident to axial movement of said axially movable element in either direction of axial motion thereofa 17. The structure defined in claim 16, wherein the means for applying a substantially steady torque to said rotatably mounted escapement element comprises a shaft extending through such element and projecting therefrom at one end thereof, means for elastically coupling said element with said shaft, means for applying torque to said shaft, said shaft being rotatable by said angular increments of rotation together with said rotatable element responsive to axial reciprocation of said axially movable escapement element, and operating means operatively affected by said shaft responsive to rotation thereof.

18. The structure defined in claim 16, together with means for axially movably mounting said coacting escapement element comprising a resilient member radially extending therefrom, and means for peripherally mounting said resilient member.

19. The structure defined in claim 16, together with means for resiliently mounting said axially movable element for predetermined axial displacement thereof, the means for axially reciprocating said axially movably mounted escapement element comprising an extension axially projecting from such element, and means for intermittently applying a force to said extension to effect axial reciprocation of said element.

20. In a numerical counter having a plurality of number wheels including a units number wheel and operating means for effecting rotation of aid units number wheel, a device for driving said operating means, said device comprising a rotatable shaft extending from said operating means, means for applying a substantially steady torque to said shaft which attempts to rotate it, a first escapement element mounted on said shaft for rotation therewith, two sets of control projections carried by said first escapement element and extending axially thereof, a second axially movably mounted escapement element carrying a set of control projections radially inwardly extending therefrom, and means for axially reciprocating said second escapement element to cause the set of radially inwardly extending control projections thereof to intercept alternately the axially extendin sets of control projections carried by said first escapement element for the purpose of allowing said torque to become effective to rotate said shaft so as to drive said operatin means by successive increments of angular rotation.

21. The structure defined in claim 20, wherein said first escapement element is rotatable on said shaft, means for elastically coupling such element with said shaft, a driven member, and means for elastically coupling said driven member with said shaft, said steady torque being applied to said driven member.

22. The structure defined in claim 26, wherein said first escapement element forms two flange like radially disposed members each carrying a set of control projections axially inwardly extending therefrom.

23. The structure defined in claim 20, wherein said first escapement element form two flangelike radially disposed members each carrying a set of control projections axially inwardly extending therefrom, said second escapement element being a tubular member which surrounds said first escapement element peripherally and carrying the set of control projections radially inwardly extending therefrom for intercepting coaction withthe sets of control projections carried by said first escapement element.

24. The structure defined in claim 20, wherein said first escapement element forms two flangelike radially disposed members each carrying a set of control projections axially inwardly extending therefrom, said second escapement element being a tubular member which surrounds said first escapement element peripherally and carrying the set of control projections radially inwardly extending therefrom for intercepting coaction with thesets of control projections carried by said first escapement element, resilient mounting means extending radially outwardly from said second escapement element, an axial extension formed by said second escapement element, a coil carried by said extension, means forming a. mag- 14 netic gap for said coil, and means for intermittently energizing said coil to effect displacement thereof relative to said gap so as to cause reciprocation of said second escapement element.

BRYAN W. CHAPIN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 351,164 Child Oct. 19, 1886 1,024,769 Ebersole Apr. 30, 1912 1,418,657 Kucharski June 6, 1922 1,487,409 Wallin Mar. 18, 1924 1,549,399 Williams Aug. 11, 1925 1,557,944 Reisbach Oct. 20, 1925 1,623,026 Cabezola Mar. 29, 1927 1,891,101 LeCount Dec. 13, 1932 2,318,359 Bellows May 4, 1943 

